Abstract
Aquatic organisms were kept in an aquarium tank containing 1 ppb of chlorophenyl-(U)-14C-DDT, 1, 2, 3, 4, 10-14C-aldrin, 2, 4-dichlorophenyl-(U)-14C-prothiophos (O-2, 4-dichlorophenyl O-ethyl S-propylphosphorodithioate), dimethyl-14C-isothioate [S-2-(isopropylthio)-ethyldimethylphosphorothiolothionate], naphthyl-1-14C-carbaryl, and N-methyl-14C-XMC (3, 5-xylyl methylcarbamate), respectively, and uptake of these pesticides in guppy (Lebistes reticulatus Peters), red snail (Indoplanorbis exustus Deshays), mosquito larvae (Culex pipiens pallens molestus Foriskal) and Daphnia pulex deGeer was investigated. Uptake of DDT by mosquito larvae was the most rapid among the aquatic organisms tested, and the snail accumulated the least in this experiment. Aldrin was rapidly transformed to dieldrin in guppy, but was scarcely found at all in Daphnia. The uptake of prothiophos was high in Daphnia, differing from the lower uptake by other organisms which easily degraded this chemical compound. The uptake of isothioate, carbaryl and XMC was fairly low, and those three pesticides were metabolized rapidly by all organisms. The uptake and metabolism of pesticides were remarkably influenced by difference of aquatic organism species and chemical variety. It was also found that the uptake of pesticides in the present experiment was different from that in the model ecosystem study which involved a food chain system.
